frozen cascade

[Moc]

They look quite well .

[kayl]

They look quite well .

thanxs moc, they are good for cascades and also autocascades

MY rotary compressors arrived today.
6x 1.5hp compressors for projects

[tim-]

nice kayl

glad to see you got those compressors, my turn to order some as well

[piotres]

How much cost one like this ? And how many BTUs it has ?

[kayl]

nice kayl

glad to see you got those compressors, my turn to order some as well

Thanxs, you will like them

How much cost one like this ? And how many BTUs it has ?

I pmed you the prices, the 1.5hp compressor is 14kBTU/heat removal. Heres the spec sheet.

[kayl]

Time to do another cascade for some wolfdale benching

2x 1.5hp Rotary compressors, r404a as the first stage refrigerant cooling a 12 plate HX feed via dual capillary.
For the second stage ill use ethylene with a shot of propane to aid in oil return.
I will use hot gas bypass with an electronic solenoid to battle the cold bug and also use a accumulator as an expansion tank to reduce the over all static pressure a little


here I have the same condenser used in my last cascade lined up against the new condenser, they say bigger is better




The electronic solenoid and the thermostat ill use to start the second stage at desired temperature

[jek666]

kayl
Will you refill oil in your compressors? They are filled with mineral oil that can be can't be used with r404... unless a shot of propane.

[tim-]

looking good kayl, i see you have been influenced by my cascade

using captube on both stages?


//tim

[teyber]

those compressors are 240vac correct?

very nice mate...

Really pathetic question, Did you say dual cap on first stage? i hear people talk about dual cap and how both lengths need to be perfect and i assumed it was for high/low side

EDIT: what oil sep is that?

beautiful cases also...

[kayl]

kayl
Will you refill oil in your compressors? They are filled with mineral oil that can be can't be used with r404... unless a shot of propane.

i just use the oil that came with the compressor, its too hard to change them in the rotary compressor unless ya got a welder and make you own access valve to drain the oil.
Like ya said a shot of propane and the oil carries nicly Winter here so i expect to see some really nice first stage temps -45c load with some luck

looking good kayl, i see you have been influenced by my cascade
using captube on both stages?//tim

Yeah finally getting off my but and doing another cascade, had most of the parts sitting here for a few months now. Im still deciding whether to do capillary line both stages like past cascades or tryt his TXv i have here. I have to get a flair kit and really want to get this build under way. So i think ill just use cap line both stages, worked well last time.

those compressors are 240vac correct?
very nice mate...
Really pathetic question, Did you say dual cap on first stage? i hear people talk about dual cap and how both lengths need to be perfect and i assumed it was for high/low side
EDIT: what oil sep is that?
beautiful cases also...

thanxs teyber, these compressors are 230w @50hz but handle 240v fine
I did dual 0.031" last unit 2.4m, i might use one length 0.042" this time as i got a roll sitting here havnt used yet, 1.8m ill try. I am using a herald oil separator with a float, worked well in last cascades, have lots of volume and separates the oil from the refrigerant really well i find.

[kayl]

Went to boc gas today and picked up a new D size bottle of ethylene
Did a little more work on the cascaade as well

[n00b 0f l337]

K you got a pipe bender?

[kayl]

K you got a pipe bender?

yeah a few years now

[kayl]

For some reason the hot gass bypass didnt work very well. Temps only dropped down to -94c at idle
So far -100c at 250w

[n00b 0f l337]

What captube you running on that second stage?

[sacha35]

Nice one Kayl -100c at 250w

[[XC] gomeler]

Might want to try a very short segment of capillary tubing setup post HX that'll dump all the R1150 from the HX and rob the evap of refrigerant. I need to re-do mine to put a solenoid on the oil return also but this does work rather nicely on my evap, it warms up very quickly. Not a perfect solution but I didn't want to dump oil laden refrigerant into the evap.

[tiborrr]

I have one n00b question regarding the quantity of 'shot of propane'. If you use R402a with mineral oil, is it okay (since R402a contains some % of R290)? How about R404a? How much is this 'shot' of propane?

[kayl]

What captube you running on that second stage?

im using 2.6m 0.031" and around 1.9m on the hot gas bypass.

Nice one Kayl -100c at 250w

Thanxs, i still have a fair amount of insulating to do so that should get a tad colder when finished

My static pressure on this unit was 200PSI, last cascade i did was closer to 300psi, so the expansion tank has really helped reduce my static pressure

Might want to try a very short segment of capillary tubing setup post HX that'll dump all the R1150 from the HX and rob the evap of refrigerant. I need to re-do mine to put a solenoid on the oil return also but this does work rather nicely on my evap, it warms up very quickly. Not a perfect solution but I didn't want to dump oil laden refrigerant into the evap.

Im still thinking not sure what way to go. But i think alot shorter length might work. I didnt want to go to short at the start as i didnt want the hotgas bypass to be too aggressive, didnt think it would have little to no effect at this length considering im pumping hot gas into the head.
Does your oil sep have a float?? I didn’t want to use to many solenoids in the cascade and only wanted one to battle the cold boot. I also didn’t want to stick cold fluids through the solenoid.

I have one n00b question regarding the quantity of 'shot of propane'. If you use R402a with mineral oil, is it okay (since R402a contains some % of R290)? How about R404a? How much is this 'shot' of propane?

the general rule ppl use is pull a vacuum then break that with r290 through the high side till ya reach 0psi on the low side then charge with r404a/r507 what ever you want. r402a only has 2% propane in their blend to carry the oil.

[[XC] gomeler]

Im still thinking not sure what way to go. But i think alot shorter length might work. I didnt want to go to short at the start as i didnt want the hotgas bypass to be too aggressive, didnt think it would have little to no effect at this length considering im pumping hot gas into the head.
Does your oil sep have a float?? I didn’t want to use to many solenoids in the cascade and only wanted one to battle the cold boot. I also didn’t want to stick cold fluids through the solenoid.

Non-floated oil separator as I thought I could do a capillary metered oil return but it's killing my suction pressures. Pumping hot gas into the head + liquid refrigerant won't work as the liquid carries such greater heat capacity vs the gaseous refrigerant. The solenoid I was using was rated down to ~-50C so I think it'll be ok as my HX chills around -40C. I was told solenoids just don't like having cold oil pushed through them as they may not reseal correctly. Sometime in the next 2 weeks I'll buy another solenoid and fix mine, if it works then that might be a route to pursue.

[kayl]

Non-floated oil separator as I thought I could do a capillary metered oil return but it's killing my suction pressures. Pumping hot gas into the head + liquid refrigerant won't work as the liquid carries such greater heat capacity vs the gaseous refrigerant. The solenoid I was using was rated down to ~-50C so I think it'll be ok as my HX chills around -40C. I was told solenoids just don't like having cold oil pushed through them as they may not reseal correctly. Sometime in the next 2 weeks I'll buy another solenoid and fix mine, if it works then that might be a route to pursue.

Be interesting to see two solenoids in action


I shortened the hot gas capillaryline to 1.2m 0.031” and added a return line 0.6m 0.031" capline to the suction line to simulate a oil separator open.
warmest it got was -84c with 80w load in 30secs and stayed around there. Let it run 3mins and switched it off, temps returned to normal.
It was interesting watching the expansion tank. Unit ran for a while before my gauges noticed a drop in pressure, then it slowly pulled down to 0psi at load.

[LittleDevil]

Really nice unit my friend!

Best Regards

[rgkpt]

congratz nice cascade

[kayl]

Thanxs guys

I benched the cascade Wednesday with a E8500 was -105c load and -108c idle
I tried benching a QX9650 on it and it cold bugs at -100c
I was using the hot gas bypass and running -94c load and then its stopped working
Now I cant hear the solenoid clicks when powered, so its not opening.
Because first turn on is a bit colder at the start and settles down, if I boot and load wprime and bench temps rise till -103c then windows crashes.
As a result I cant bench this cpu on this cascade.
Heres the insides finished.

[n00b 0f l337]

How long to pulldown to that? You once said 15 minutes on a cascade, and what sorta vacuum you running on second stage?